The objective of this research project is to study the properties, both physical and chemical of drugs and related molecules known to be photosensitizers. It is hoped that from these properties, generalizations and predictions can be made about these and other molecules with regard to the property of photosensitization. With this knowledge, potential drugs, whether they be for mental patients, cancer, malaria etc., which possess this undesirable property, can be modified to still preserve their therapeutic properties but remove this undesirable property. Also we wish to investigate the phenomenon known as photodynamic action.